• Study examined men’s ejaculate after watching sexually explicit films
• Found ejaculation was faster and sperm quality better when the men watched clips involving a new, different looking woman 
• Experts warn male infertility could be under-diagnosed because samples used for testing are commonly produced using new female images
• Suggest sperm tested could therefore be better quality, misleading results

Men who have sex with new partners are more likely to reach orgasm faster and will produce better quality sperm, scientists believe.

A study has shown that sperm health is improved when men have encounters with unfamiliar women.

And researchers at The College of Wooster in Ohio hope their findings will help to improve treatments for fertility

Men who have sex with new partners are more likely to reach orgasm faster and will produce better quality sperm, a new study by scientists at The College of Wooster in Ohio found

Quantity, movement and structure all aid sperm health.

Writing in the journal Evolutionary Psychological Science, researchers said they believe these traits may change for the better, with new sexual partners.

‘Our findings are the first to demonstrate that men’s ejaculate behaviour and composition change in response to novel female stimulus,’ the team led by Paul Joseph said.